Re: bad estimation together with large work_mem generates terrible slow hash joins - Mailing list pgsql-hackers

From Tomas Vondra
Subject Re: bad estimation together with large work_mem generates terrible slow hash joins
Date
Msg-id 5410A2A5.9010100@fuzzy.cz
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In response to Re: bad estimation together with large work_mem generates terrible slow hash joins  (Heikki Linnakangas <hlinnakangas@vmware.com>)
Responses Re: bad estimation together with large work_mem generates terrible slow hash joins
List pgsql-hackers
On 10.9.2014 20:25, Heikki Linnakangas wrote:
> On 09/10/2014 01:49 AM, Tomas Vondra wrote:
>> I also did a few 'minor' changes to the dense allocation patch, most
>> notably:
>>
>> * renamed HashChunk/HashChunkData to MemoryChunk/MemoryChunkData
>>    The original naming seemed a bit awkward.
> 
> That's too easy to confuse with regular MemoryContext and AllocChunk
> stuff. I renamed it to HashMemoryChunk.

BTW this breaks the second patch, which is allocating new chunks when
resizing the hash table. Should I rebase the patch, or can the commiter
do s/MemoryChunk/HashMemoryChunk/ ?

Assuming there are no more fixes needed, of course.

Tomas




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